The invention generally relates to a transmission providing an uninterrupted transition from high torque to high speed operation.
Transmissions commonly operate in both high torque, low speed and low torque, high speed situations. At start up of an associated vehicle the transmission is moving at low speeds with a higher torque output required by the vehicle. As the speed of the vehicle and transmission increases lower torque output from the transmission is required. Typically, when transferring from high torque to high speed operation the transmission requires at least one shift to change the gear ratios. Each time a gear shift occurs the output of power from the transmission is momentarily interrupted.
To reduce the number of such power interruptions, continuously variable transmissions have been utilized. Continuously variable transmissions employ electric motors to provide input to the transmission at low speeds. Use of the electric motor provides a greater range of operating speed for the transmission before a gear shift is required. However, while greater ranges of transmission speeds are available, known designs are limited in the amount of torque available at the output of the transmission. Thus, using continuously variable transmission in applications requiring high torque is not always practical.
An improved arrangement for providing a continuously variable transmission which allows an uninterrupted transition from high torque to high speed is needed.